Posts Tagged: Xerces Society

It's good to see so many publications focusing on the pollinator crisis--because that's exactly what it is, a crisis.

Writing for the Naturejournal, Sharon Levy recently examined pollination studies that focus on the importance of pollinators and the plants they frequent.

Levy mentioned the work of conservation biologist Claire Kremen of UC Berkeley; Rachael Winfree, a pollination biologist at Rutgers University in New Brunswick, N.J.; and native pollinator specialist Neal Williams of UC Davis.

Williams led one of the studies that found that "most native bees are far less picky than was imagined," Levy wrote. The study showed that "bees collect pollen from both alien and native plants in proportion to a plant's abundance in the landscape," she related. "In highly disturbed habitats, bees make greater use of alien plants--not because the bees prefer them, but simply because introduced plants are far more common where people have transformed the landscape."

Last year Williams received a three-year federally funded research grant aimed at improving pollinator habitat plantings in nationwide agricultural settings. Williams said at the time:

“Recent declines in honey bee populations and the threat of losses in pollination service to economically important crops has raised awareness of the importance of restoring and conserving native bee diversity and abundance. We will be developing simplified assessment tools that will allow land stewards to evaluate the cost-effectiveness of future habitat restorations."

In 2000, the economic value of insect-pollinated crops in the United States was estimated at $18.9 billion.

Kremen, Winfree, Williams and Mace Vaughan, pollinator program director of the Xerces Society for Invertebrate Conservation, were among the specialists sharing their expertise at the 59th annual Entomological Society of America's meeting, held Nov. 13-16 in the Reno-Sparks Convention Center.

At one of the ESA seminars, Winfrey said that about 75 percent of the nation's crops require pollination, and that there are 20,000 species of native bees.

Kremen pointed out that "35 percent of the food we eat is pollinated by bees."

To attract native pollinators, the Xerces Society says that we need to:--Ensure pollination in our gardens, orchards or farms.--Identify the flower-visiting insects of our region.--Provide host plants and nesting sites for bees and butterflies.--Create a landscape that is beautiful, diverse and pollinator friendly.

Good advice. We all have a role to fulfill in attracting and protecting the pollinators.

At the UC Davis Department of Entomology, we're frequently contacted by folks throughout the country asking what to plant to attract pollinators--native bees, honey bees (honey bees not native; European colonists brought them over here in 1622), and other pollinators.

The Xerces Society for Invertebrate Conservation has a wonderful list of native plants on its website. You click on your region and you'll be directed to a list.

If you poke around the Xerces Society website, you can find information on why native bee habitats are important and how to create native bee habitats. Also check out the pollinator handbook and the fact sheets.

Xerces Society scientists just developed a first-of-its-kind conservation strategy summarizing the threats facing native bees in the diverse landscapes of Yolo County and identifying measures to protect them.

And what a great conservation--and conservation--piece this is.

Their 70-page paper, Yolo Natural Heritage Program Pollinator Conservation Strategy, is designed to protect such wild bees as bumble bees, leafcutter bees, mason bees, blue orchard bees and others. (You can download the paper from the Xerces Society Web site and from the Yolo Natural Heritage Program Web site.)

“Whether you manage roadsides or run a farm there are actions that you can take to improve the health of pollinators,” says Matthew Shepherd, Xerces Society senior conservation associate and co-author of the report. “Identifying and protecting floral resources can provide significant benefit to the native bees and other pollinators in Yolo County.”

The project, funded in part by a grant from the California Department of Fish and Game, provides land managers with information vital to "save the pollinators" of Yolo County. The county includes six major landscapes: agriculture, grasslands, woodlands, shrubland and scrub, riparian and wetland, and urban and barren.

As the scientists point out, some 60 to 90 percent of the world's flowering plants depend on animals for pollination, and most of these animals are insects.

"Research shows that native bees contribute substantially to the pollination of many crops, including watermelon, canola, sunflower, and tomatoes," the report says. "The value of crop pollination by native, wild bees in the United States is estimated at $3 billion. In Yolo County, extensive studies demonstrate the significant role of native pollinators in the economic viability of agriculture. In addition, native bees provide incalculable value as pollinators of native plants."

Among the many contributors to this report: native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis; and UC Berkeley conservation biologist Claire Kremen, an affiliate of the UC Davis Department of Entomology.

This is a report well-worth reading, and even more importantly, following the measures listed to protect the health of our native bees. These beneficial insects need flowers for foraging and nest sites to raise their young. Some 70 percent of native bee species nest in the ground. Most of the others nest in cavities in trees or plant stems. "Bumble bees require a small cavity such as an abandoned rodent hole," the report indicates.

So, that black-faced bumble bee (Bombus californicus) that you see gathering pollen on a California poppy may go home to...well...a rat hole.

All the more reason to become more observant and pro-active of their needs.

The bumble bee population is declining and some species are teetering on the brink of extinction.

That's the gist behind why three conservation groups and bumble bee researcher Robbin Thorp, emeritus professor of entomology at UC Davis, are asking the federal government to impose regulations on the movement and health of commercial bumble bees to protect the declining native/wild bumble bee population.

A Jan. 12th press release issued by the Xerces Society for Invertebrate Conservation is drawing worldwide attention. The latest coverage came from the New York Times and the Washington Post.

Take Franklin's bumble bee. That's a bumble bee found only in a small stretch of southern Oregon and northern California. Robbin Thorp, a member of the Xerces Society, hasn't seen it for several years and fears it may be extinct.

You'll want to read the article on "Bumble Bees in Decline" on the Xerces Society Web site and look at the photos of the bumble bees that could be nearing extinction.

Two recent studies provide a direct link between diseases in commercial bumble bees and the health of wild bumble bees: